Automatic pressure and vacuum clearing skid method

ABSTRACT

A method of pressurization and evacuation of a system including during a pressurization phase; introducing a pressurized gas stream into the top valve, which is actuated to direct the pressurized gas stream into the bottom valve, wherein the bottom valve is actuated to direct the pressurized gas stream to the customer apparatus; and during a vacuum phase; introducing the pressurized gas stream into the top valve, which is actuated to direct the pressurized gas stream into the inlet port of the pressure inlet of the educator, thereby producing a low pressure condition in the suction inlet, introducing a customer gas stream into the bottom valve, which is actuated to direct the customer gas to exit the bottom valve, wherein the low pressure condition causes the customer gas stream to be directed to the educator suction inlet, wherein it mixes with the pressurized gas stream and exits the educator discharge outlet.

BACKGROUND

In industrial chemical and petrochemical processes, gaseous nitrogen is used for a number of purposes. Nitrogen is largely inert, and as such is commonly used to displace undesired gases in various processes. One common example is the use of gaseous nitrogen to displace air as an inert blanket. Nitrogen does engage in certain chemical reactions and, for example, is useful in the production of ammonia. Gaseous nitrogen is often provided to the end user as a commodity, for example by means of an “over the fence” supply from an existing nitrogen pipeline or from a tanker truck. Many processes that use nitrogen are have pressure limitations, either high, low, or both, that must be maintained.

SUMMARY

In another embodiment of the present invention, a method of pressurization and evacuation of a system including during a pressurization phase; introducing a pressurized gas stream into the top valve, which is actuated to direct the pressurized gas stream into the bottom valve, wherein the bottom valve is actuated to direct the pressurized gas stream to the customer apparatus; and during a vacuum phase; introducing the pressurized gas stream into the top valve, which is actuated to direct the pressurized gas stream into the inlet port of the pressure inlet of the educator, thereby producing a low pressure condition in the suction inlet, introducing a customer gas stream into the bottom valve, which is actuated to direct the customer gas to exit the bottom valve, wherein the low pressure condition causes the customer gas stream to be directed to the educator suction inlet, wherein it mixes with the pressurized gas stream and exits the educator discharge outlet.

BRIEF DESCRIPTION OF THE FIGURES

For a further understanding of the nature and objects for the present invention, reference should be made to the following detailed description, taken in conjunction with the accompanying drawings, in which like elements are given the same or analogous reference numbers and wherein:

FIG. 1 illustrates a schematic representation of the system indicating the ports, inlets, and outlet on the 3-way valves and the eductor, in accordance with one embodiment of the present invention.

FIG. 2 illustrates a schematic representation of the pressurization phase, in accordance with one embodiment of the present invention.

FIG. 3 illustrates a schematic representation of the vacuum phase, in accordance with one embodiment of the present invention.

FIG. 4 illustrates a representation of the top 3-way valve and the bottom 3-way valve with individual actuators, in accordance with one embodiment of the present invention.

FIG. 5 illustrates a representation of the top 3-way valve and the bottom 3-way valve with a single actuator, in accordance with one embodiment of the present invention.

FIG. 6 illustrates a representation of the valves indicating the port orientations in the pressurization phase, in accordance with one embodiment of the present invention.

FIG. 7 illustrates a representation of the valves indicating the port orientations in the vacuum phase, in accordance with one embodiment of the present invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

Illustrative embodiments of the invention are described below. While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must be made to achieve the developer's specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.

ELEMENT LEGEND

-   -   101=Gas Source (Nitrogen, etc) entering First Port of Top 3-Way         Valve     -   102=Top 3-Way Valve     -   103=First conduit     -   104=Second conduit     -   105=First Check Valve     -   107=Bottom 3-Way Valve     -   108=Fourth conduit     -   109 a=Stream to Customer Equipment (apparatus)     -   109 b=Stream from Customer Equipment     -   110=First Pressure Safety Valve     -   111=Second Check Valve     -   113=Second Pressure Safety Valve     -   114=Eductor     -   115=Third conduit     -   116=Stream to Flare     -   117=Pressure Indicator     -   118=Top 3-way valve first port     -   119=Top 3-way valve second port     -   120=Top 3-way valve third port     -   121=Bottom 3-way valve first port     -   122=Bottom 3-way valve second port     -   123=Bottom 3-way valve third port     -   124=Eductor pressure inlet     -   125=Eductor suction inlet     -   126=Eductor discharge outlet     -   127=First actuator (Top 3-way valve)     -   128=Second actuator (Bottom 3-way valve)     -   129=Common actuator (Top 3-way valve and Bottom 3-way valve)

Turning to FIG. 1, a pressurization and evacuation system is presented. The system includes a top 3-way valve 102 that includes a first port 118, a second port 119, and a third port 120. The system includes a bottom 3-way valve 107 that includes a first port 121, a second port 122, and a third port 123. The system also includes an educator 114 comprising a pressure inlet 124, a suction inlet 125, and a discharge outlet 126.

The top 3-way valve third port 120 is fluidically connected with the educator pressure inlet 124 by with a first conduit 103. The first conduit 103 may also include a second check valve 111 in fluidic connection with the top 3-way valve third port 120 and the educator pressure inlet 124. The first conduit may include a second pressure safety valve 113 in fluidic connection with the first conduit.

The top 3-way valve second port 119 is fluidically connected with the bottom 3-way valve first port 121 by a second conduit 104. The second conduit 104 may also include a first check valve 105 in fluidic connection with the top 3-way valve second port 119 and the bottom 3-way valve first port 121.

The bottom 3-way valve third port 123 is fluidically connected with the educator suction inlet 125 with a third conduit 115. The bottom 3-way valve second port 122 is connected with a customer apparatus (not shown) with a fourth conduit 108. The fourth conduit 108 may include a first pressure safety valve 110.

As indicated in FIG. 4, the top 3-way valve 102 may be controlled by a first actuator 127, and the bottom 3-way valve 107 may be controlled by a second actuator 128. As indicated in FIG. 5, the top 3-way valve 102 and the bottom 3-way valve 107 may be controlled by a common actuator 129. The first actuator 127 and/or the second actuator 128 and/or the common actuator may be of a type selected from the group consisting of an electric actuator, a pneumatic actuator, and a hydraulic actuator. In the interest of simplicity, FIGS. 6 and 7 indicate a common actuator, but one of ordinary skill in the art will readily understand how such an arrangement may also be operated with 3-way valves operated by separate actuators.

The system may include a pressure indicator 117 that is in fluidic connection with the fourth conduit 108. The pressure indicator 117 may provide a signal to the top 3-way valve 102, and/or the pressure indicator may provide a signal to the bottom 3-way valve 107.

Turning to FIG. 2, a pressurization method is presented, utilizing the system as described above. During the pressurization phase a pressurized gas stream 101 is introduced into the first port 118 of the top 3-way valve 102. The top 3-way valve 102 is then actuated to direct the pressurized gas stream 101 to exit the second port 119 of the top 3-way valve 102 and enter second conduit 104. Downstream of the second port 119 of the top 3-way valve may be a first check valve 105 in order to prevent back flow.

The pressurized gas stream from second conduit 104 is introduced into the first port 121 of the bottom 3-way valve 107, the bottom 3-way valve 107 is then actuated to direct the pressurized gas stream to exit the second port 122 of the bottom 3-way valve 107 and to enter fourth conduit 108. Downstream of the second port 122 of the bottom 3-way valve 107 may be a pressure indicator 117 and/or a first pressure safety valve 110. The pressurized gas then exits fourth conduit 108 and enters the customer apparatus (not shown).

Turning to FIG. 3, a vacuum method is presented, utilizing the system as described above. During the vacuum phase the pressurized gas stream 101 is introduced into the first port 118 of the top 3-way valve 102. The top 3-way valve 102 is then actuated to direct the pressurized gas stream to exit the third port 120 of the top 3-way valve 102 and enter first conduit 103. Downstream of the third port 120 of the top 3-way valve may be a second check valve 111 in order to prevent back flow, and/or a second pressure safety valve 113.

The pressurized gas stream from the first conduit 103 is introduced into the educator pressure inlet 124, thus producing a low pressure condition in the suction inlet. A customer gas steam 109 a is then introduced into the second port 122 of the bottom 3-way valve 107. The bottom 3-way valve 107 is then actuated to direct the customer gas to exit the third port 123 of the bottom 3-way valve 107. The low pressure condition then causes the customer gas stream to be directed to the educator suction inlet 125, wherein it mixes with the pressurized gas stream 124 and exits the educator discharge outlet 126 and to a conduit to exhaust or flare 116. The pressurized gas stream may be an inert gas. The pressurized gas stream may be nitrogen.

Turning to FIG. 4, the top 3-way valve 102 may be controlled by a first actuator 127, and the bottom 3-way valve 107 may be controlled by a second actuator 128. Either the first actuator 127 or the second actuator 128, or both actuators, may be an electric actuator, a pneumatic actuator, or a hydraulic actuator.

Turning to FIG. 5, the top 3-way valve 102 and the bottom 3-way valve 107 may be controlled by a common actuator 129. Either the common actuator 129 may be an electric actuator, a pneumatic actuator, or a hydraulic actuator.

One embodiment of the respective valve port orientation and status for a single actuator arrangement for the pressurization phase is illustrated in FIG. 6. One embodiment of the respective valve port orientation and status for a single actuator arrangement for the vacuum phase is illustrated in FIG. 7. One of ordinary skill in the art will readily understand how such an arrangement may also be operated with 3-way valves operated by separate actuators.

Turning to FIGS. 2 and 3, a pressure indicator 117 may be in fluidic connection with the fourth conduit 108, and the pressure indicator 117 may provide a signal to the first actuator 127 and/or the second actuator 128. The vacuum phase may be initiated when the pressure indicator 117 senses a pressure above a first predetermined threshold. The pressurization phase may be initiated when the pressure indicator 117 senses a pressure below a second predetermined threshold. The system begins normal operation with the pressure indicator 117 at ambient pressure.

It will be understood that many additional changes in the details, materials, steps and arrangement of parts, which have been herein described in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims. Thus, the present invention is not intended to be limited to the specific embodiments in the examples given above. 

What is claimed is:
 1. A method of pressurization and evacuation of a system comprising: a pressurization and evacuation system comprising: a top 3-way valve comprising a first port, a second port and a third port, a bottom 3-way valve comprising a first port, a second outlet port and a third port, and an eductor comprising a pressure inlet, a suction inlet, and a discharge outlet, wherein: a first conduit fluidically connects the top 3-way valve third port with the eductor pressure inlet, a second conduit fluidically connects the top 3-way valve second port with the bottom 3-way valve first port, a third conduit fluidically connects the bottom 3-way valve third port with the eductor suction inlet, and a fourth conduit fluidically connects the bottom 3-way valve second port with a customer apparatus, the method comprising, during a pressurization phase: introducing a pressurized gas stream into the first port of the top 3-way valve, wherein the top 3-way valve is actuated to direct the pressurized gas stream to exit the second port of the top 3-way valve, introducing the pressurized gas stream into the first port of the bottom 3-way valve, wherein the bottom 3-way valve is actuated to direct the pressurized gas stream to exit the second port of the bottom 3-way valve and to the customer apparatus; the method comprising, during a vacuum phase: introducing the pressurized gas stream into the first port of the top 3-way valve, wherein top 3-way valve is actuated to direct the pressurized gas stream to exit the third port of the top 3-way valve, introducing the pressurized gas stream into an inlet port of the pressure inlet of the eductor, thereby producing a low pressure condition in the suction inlet, introducing a customer gas stream into the second port of the bottom 3-way valve, wherein the bottom 3-way valve is actuated to direct the customer gas to exit the third port of the bottom 3-way valve, wherein the low pressure condition causes the customer gas stream to be directed to the eductor suction inlet, wherein it mixes with the pressurized gas stream and exits the eductor discharge outlet.
 2. The method of pressurization and evacuation of a system of claim 1, wherein the pressurized gas stream comprises an inert gas.
 3. The method of pressurization and evacuation of a system of claim 2, wherein the inert gas is nitrogen.
 4. The method of pressurization and evacuation of a system of claim 1, wherein the top 3-way valve is controlled by a first actuator, and the bottom 3-way valve is controlled by a second actuator.
 5. The method of pressurization and evacuation of a system of claim 4, wherein the first actuator is of a type selected from the group consisting of an electric actuator, a pneumatic actuator, and a hydraulic actuator.
 6. The method of pressurization and evacuation of a system 4, wherein the second actuator is of a type selected from the group consisting of an electric actuator, a pneumatic actuator, and a hydraulic actuator.
 7. The method of pressurization and evacuation of a system of claim 1, wherein the top 3-way valve and the bottom 3-way valve are controlled by a single actuator.
 8. The method of pressurization and evacuation of a system of claim 7, wherein the single actuator is of a type selected from the group consisting of an electric actuator, a pneumatic actuator, and a hydraulic actuator.
 9. The method of pressurization and evacuation of a system of claim 4, further comprising a pressure indicator in fluidic connection with the fourth conduit, wherein the pressure indicator provides a signal to the first motor, and wherein the pressure indicator provides a signal to the second motor.
 10. The method of pressurization and evacuation of a system of claim 9, wherein the vacuum phase is initiated when the pressure indicator senses a pressure above a first predetermined threshold.
 11. The method of pressurization and evacuation of a system of claim 10, wherein the pressurization phase is initiated when the pressure indicator senses a pressure below a second predetermined threshold. 